package com.kaoshi.myweb.common.utils;

import java.io.UnsupportedEncodingException;
import java.net.URLDecoder;

/**
 * 描述: 字符编码工具类
 * 版权: Copyright (c) 2010 
 * 公司: 思迪科技 
 * 作者: 易庆峰
 * 版本: 1.0 
 */
public class CharHelper
{
	
	
	/**
	 * 转换编码 ISO-8859-1到GB2312
	 * @param text
	 * @return
	 */
	public static String ISO2GB(String text)
	{
		String result = "";
		try
		{
			result = new String(text.getBytes("ISO-8859-1"), "GB2312");
		}
		catch (UnsupportedEncodingException ex)
		{
			result = ex.toString();
		}
		return result;
	}
	
	
	
	/**
	 * 转换编码 GB2312到ISO-8859-1
	 * @param text
	 * @return
	 */
	public static String GB2ISO(String text)
	{
		String result = "";
		try
		{
			result = new String(text.getBytes("GB2312"), "ISO-8859-1");
		}
		catch (UnsupportedEncodingException ex)
		{
			ex.printStackTrace();
		}
		return result;
	}
	
	/**
	 * Utf8URL编码
	 * @param s
	 * @return
	 */
	public static String Utf8URLencode(String text)
	{
		StringBuffer result = new StringBuffer();
		
		for (int i = 0; i < text.length(); i++)
		{
			
			char c = text.charAt(i);
			if (c >= 0 && c <= 255)
			{
				result.append(c);
			}
			else
			{
				
				byte[] b = new byte[0];
				try
				{
					b = Character.toString(c).getBytes("UTF-8");
				}
				catch (Exception ex)
				{
				}
				
				for (int j = 0; j < b.length; j++)
				{
					int k = b[j];
					if (k < 0)
						k += 256;
					result.append("%" + Integer.toHexString(k).toUpperCase());
				}
				
			}
		}
		
		return result.toString();
	}
	
	
	
	/**
	 * Utf8URL解码
	 * @param text
	 * @return
	 */
	public static String Utf8URLdecode(String text)
	{
		String result = "";
		int p = 0;
		
		if (text != null && text.length() > 0)
		{
			text = text.toLowerCase();
			p = text.indexOf("%e");
			if (p == -1)
				return text;
			
			while (p != -1)
			{
				result += text.substring(0, p);
				text = text.substring(p, text.length());
				if ("".equalsIgnoreCase(text) || text.length() < 9)
					return result;
				
				result += CodeToWord(text.substring(0, 9));
				text = text.substring(9, text.length());
				p = text.indexOf("%e");
			}
			
		}
		
		return result + text;
	}
	
	
	
	/**
	 * utf8URL编码转字符
	 * @param text
	 * @return
	 */
	private static String CodeToWord(String text)
	{
		String result;
		
		if (Utf8codeCheck(text))
		{
			byte[] code = new byte[3];
			code[0] = (byte) (Integer.parseInt(text.substring(1, 3), 16) - 256);
			code[1] = (byte) (Integer.parseInt(text.substring(4, 6), 16) - 256);
			code[2] = (byte) (Integer.parseInt(text.substring(7, 9), 16) - 256);
			try
			{
				result = new String(code, "UTF-8");
			}
			catch (UnsupportedEncodingException ex)
			{
				result = null;
			}
		}
		else
		{
			result = text;
		}
		
		return result;
	}
	
	
	
	/**
	 * 编码是否有效
	 * @param text
	 * @return
	 */
	private static boolean Utf8codeCheck(String text)
	{
		String sign = "";
		if (text.startsWith("%e"))
			for (int i = 0, p = 0; p != -1; i++)
			{
				p = text.indexOf("%", p);
				if (p != -1)
					p++;
				sign += p;
			}
		return sign.equals("147-1");
	}
	
	
	
	/**
	 * 是否Utf8Url编码
	 * @param text
	 * @return
	 */
	public static boolean isUtf8Url(String text)
	{
		text = text.toLowerCase();
		int p = text.indexOf("%");
		if (p != -1 && text.length() - p > 9)
		{
			text = text.substring(p, p + 9);
		}
		return Utf8codeCheck(text);
	}
	
	
	
	/**
	 * 测试
	 * @param args
	 */
	public static void main(String[] args)
	{
		
		CharHelper charTools = new CharHelper();
		
		String url;
		
		url = "http://www.google.com/search?hl=zh-CN&newwindow=1&q=%E4%B8%AD%E5%9B%BD%E5%A4%A7%E7%99%BE%E7%A7%91%E5%9C%A8%E7%BA%BF%E5%85%A8%E6%96%87%E6%A3%80%E7%B4%A2&btnG=%E6%90%9C%E7%B4%A2&lr=%E8%82%A1%E7%A5%A8%E5%9E%8B";
		String tzdx = "%E8%82%A1%E7%A5%A8%E5%9E%8B";
		System.out.println(charTools.Utf8URLdecode(tzdx));
		if (charTools.isUtf8Url(url))
		{
			System.out.println(charTools.Utf8URLdecode(url));
		}
		else
		{
			System.out.println(URLDecoder.decode(url));
		}
		
		url = "http://www.baidu.com/baidu?word=%D6%D0%B9%FA%B4%F3%B0%D9%BF%C6%D4%DA%CF%DF%C8%AB%CE%C4%BC%EC%CB%F7&tn=myie2dg";
		if (charTools.isUtf8Url(url))
		{
			System.out.println(charTools.Utf8URLdecode(url));
		}
		else
		{
			System.out.println(URLDecoder.decode(url));
		}
		
	}
	
}
